This model of a steel trestle was designed by scaling some photographs and a number of measurements of the steel trestle at Tamworth NSW.
This model trestle is 17 feet 6 inches high (including the concrete base), eight feet wide at the top, 15 feet 10 inches at the top of the concrete base with a 19 foot 6 inch by 2 foot 8 inch by 16 inch high concrete base. Due to some confusion with the recorded dimensions the base of the trestle is 1 foot 7 inches wider than the prototype. This was only found later when checking everything, my fault. The extra width doesn't seem to throw the proportions out though, it still looks right. Due to the many, many hours in the design the error was left as a complete re-draw would have been required.
Some dimensions have been modified to ensure that the model would be able to be printed this includes the thickness of the edges of L and channel sections.
If I have counted correctly there are 394 rivets on the model trestle.
The Tamworth trestles appear to be supporting standard 35 foot long plate girders.